Communications networks, including the Internet, have been used to access resources located on various network access devices. Typically, a user may transfer data files, including text, application files, voice and video with electronic network access devices. As the size and complexity of available communications networks has increased, methods of conveniently transferring data across various software platforms have been sought.
In order to deliver a message to an agent via an electronic communications network, it is necessary to address the computer and the application software accessed by the agent. Typically, an Internet Protocol (IP) address is used to identify the computer. Application software is commonly addressed to a port number on the computer. A computer may have thousands of ports available. Each port can connect to only one application. However, an application may connect to multiple ports. A combination of the IP address and port number allows a message to be delivered properly to a designated application program. In this way, an Internet message is first delivered to an IP address associated with a computer and then delivered to the specific port on the computer running application software associated with the message.
Fixed IP addresses are not widely available to independent users. It is common for domestic and small business users to access a network such as the Internet via an Internet Service Provider (ISP). ISPs can act as a redirecting service and assign a temporary IP address to a computer contacting the service provider. The temporary IP address is used by that computer during one contiguous computing session. When a computing session ends, the ISP, or other re-directing service, makes a previously allocated computer address available to a subsequent request to initiate an Internet computing session. An address is consistent for a user during any continuous computing session.
Similarly, port numbers are not commonly allocated on a fixed basis. On a shared processor, such as a mainframe, shared port numbers are allocated to application programs as various users invoke the applications. On single user machines such as PCs, all port numbers are available to a user. However, multiple instances of an application program may be enabled for concurrent execution. Each instance must be assigned a unique port Ports are therefore assigned on an as-requested basis.
Due to the allocation and re-allocation of IP addresses and port numbers with each new computing session, it is difficult for a user to track the address of another party with which the user may wish to communicate. Without an address, it is difficult to communicate directly across a network.
In response to the problem of changing addresses, systems have been implemented using centralized servers that maintain ii permanent IP address and port number. Often, specially designated programs may be allocated a port number for that special program's permanent exclusive use. In this way, an agent can locate the centralized server and communicate with it. If appropriate, the centralized server can forward a message to another agent who has also identified itself to the communications server. The centralized server acts as a hub for all communication. However, if the centralized server or a communications link to the server should fail, all communications cease.
In addition, permanent address centralized servers typically require set up and maintenance by technical personnel. Applications running on the servers, such as an email or database application, may require a particular computing platform to execute the application software. With the proliferation of computing platforms such as Microsoft Windows, Unix, DOS, and IBM OS2, it becomes increasingly difficult to support multiple platforms.
Multiple services in the form of resources and applications can be available on a network. Typically, a discrete service requires a unique access interface. In addition, different operating systems are often manifested in different interfaces.
It would be useful therefore to have a method of communicating that does not require a centralized server and is executable across multiple platforms.